We know, it's a little crazy that there is an entire holiday dedicated to the idea that there is life on other planets. However, there are so many among us who believe there's intelligent out there, why not give them a day?

We mean, even some of our favorite A-listers have admitted to believing aliens — no joke!

Not to mention, ever since NASA announced that there were several Earth-sized planets located in the TRAPPIST-1 system, many believers in extraterrestrial life think the existence of aliens may be confirmed sooner than later. So, in honor of Alien Day, be sure to ch-ch-check out the full list of celebs who believe aliens (below)!